Vehicle suspension device

ABSTRACT

A vehicle suspension device comprising a telescopic shock absorber including an elongated tubular housing, a piston reciprocable within the housing and connected to one end of a piston rod extending axially outwardly from one end of the housing, a tubular dirt shield supported on one end of the piston rod and extending coaxially of the rod and the housing, a helical coil spring extending coaxially of the housing and the dirt shield with the dirt shield being disposed entirely within the confines of the coil spring, and first and second spring supports located on the dirt shield and the exterior of the housing for operatively supporting the coil spring in its proper position around the shock absorber.

SUMMARY OF THE INVENTION

This invention relates generally to vehicle suspension devices and moreparticularly, to a new and improved combination hydraulic shock absorberand coil spring arrangement for use in the suspension systems ofautomotive vehicles and the like.

It is accordingly a general object of the present invention to provide anew and improved suspension device for automotive vehicles and the like.

It is a more particular object of the present invention to provide a newand improved combination hydraulic shock absorber and coil springarrangement which may be incorporated in the suspension systems ofautomotive vehicles.

It is still a more particular object of the present invention to providea new and improved arrangement for operatively supporting and orientinga helical coil spring relative to the shock absorber dirt shield.

It is yet another object of the present invention to provide a new andimproved vehicle suspension device, as above described, incorporating anovel means for attaching the coil spring upon the shock absorberhousing.

It is another object of the present invention to provide a new andimproved vehicle suspension device of the above-described type which isof a relatively simple design, is economical to commercially manufactureand which will have a long and effective operational life.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a longitudinal cross-sectional view of the vehicle suspensiondevice of the present invention;

FIG. 2 is an exploded assembly view of the dirt shield, coil spring andspring support flanges incorporated in the suspension device shown inFIG. 1, and

FIG. 3 is a transverse cross-sectional view taken substantially alongthe line 3--3 of FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring now in detail to the drawing, and in particular to FIG. 1thereof, a vehicle suspension device 10, in accordance with onepreferred embodiment of the invention, is shown as including a hydraulicdirect acting telescopic shock absorber 12 comprising an elongatedtubular pressure cylinder 14 that defines an internal working chamber16. Disposed within the chamber 16 is a valved piston 18 which isfixedly secured to a reduced diameter end portion 20 of an elongatedreciprocable piston rod 22 that extends axially upwardly from the upperend of the pressure cylinder 14 and is reciprocable concomitantly withthe piston 18 in a manner well known in the art. The piston rod 22 hasthe upper end thereof extending through a central opening 24 in acombination rod guide and seal assembly, generally designated by thenumeral 26, which functions to close the upper end of the chamber 16 andslidably and sealingly support the piston rod 22 for reciprocal movementrelative thereto. Disposed around the outer periphery of the pressurecylinder 14 is a concentric tubular reserve tube or housing 28 which iscoextensive of the pressure cylinder 14 and defines a fluid reservoir 30therewith. The reservoir 30 is communicable with the chamber 16 via abase valve assembly, generally designated 32, which is located at thelower end of the pressure cylinder 14 and functions to selectivelycontrol the flow of fluid between the reservoir 30 and chamber 16. Theupper and lower ends of the shock absorber 12 are closed by conventionalend caps 34 and 36, which are operatively secured, as by welding or thelike, to the opposite ends of the housing 28. Means in the form ofsuitable attachment fittings or the like 38 and 40 are provided on theouter or terminal end of the piston rod 22 and the end cap 36,respectively, for securing the suspension device 10 of the presentinvention to the sprung and unsprung portions of the associated vehiclein a manner well known in the art.

For purposes of conciseness of description, the piston 18 and base valveassembly 32 are of substantially the same construction and operation asthe analogous components in U.S. Pat. No. 3,771,626, owned by theassignee of this application and the disclosure of which is incorporatedby reference herein.

As best seen in FIG. 1, the suspension device 10 is provided with anelongated cylindrical dirt shield assembly, generally designated by thenumeral 42 which includes a tubular dirt shield member 44 that isarranged concentrically of the upper end of the piston rod 22 andhousing 28. The upper end of the dirt shield 44 is fixedly secured tothe adjacent end of the piston rod 22 by means of a generally cup-shapedend cap 46 that is secured to the dirt shield member 44, as by weldingor the like. The end cap 46 is formed with a central opening 48 throughwhich the upper end of the piston rod 42 extends, with the upper fitting38 being secured as by welding or the like to the upper side of the endcap 46. The upper end of the dirt shield member 44 is formed with aradially outwardly extending shoulder 50 which functions in a mannerhereinafter to be described in operatively supporting an elongatedhelical coil spring 52 which is arranged concentrically of the shockabsorber 12, as illustrated. The coil spring 52 is preferably of thevariable rate type and as such, comprises varying members of springconvolutions 54 along the length thereof. In a preferred construction ofthe present invention, the greater number of convolutions 54 of thespring 52 are located in axial registry or alignment with the housing28, i.e. at the lower end of the spring 52, in order to minimizeabrasion between the inner periphery of the spring 52 and the dirtshield assembly 42 during operation of the suspension device 10. Thespring 52 is provided with upper and lower terminal ends 56 and 58,respectively, the former of which is adapted to be supported by an upperspring support flange, generally designated by the numeral 60. Theflange 60 includes a generally axially extending annular section 62which terminates at the upper end thereof in an integral radiallyextending section 64. The inner diameter of the flange 60 is larger thanthe outer diameter of the dirt shield member 42 but is smaller indiameter than the shoulder 50 formed in the upper end thereof, wherebythe flange 60 may be forced upwardly under the influence of the spring52 and be fixedly retained in abutting engagement with the shoulder 50.As best seen in FIG. 1, a resilient bearing pad 66 is interposed betweenthe radial section 64 of the flange 60 and the upper end 56 of thespring 52.

The lower end of the coil spring 52 is operatively supported by means ofa lower spring support flange, generally designated 68 which is adaptedto be secured to the outer periphery of the housing 28. The flange 68 issimilar to the aforedescribed flange 60 and as such comprises agenerally axially extending section 70 which terminates at the lower endthereof in a radially outwardly extending section 72. The flange 68 issupported at a position generally axially aligned with the radiallyoutwardly extending shoulder 74 formed in the reserve tube 28.Interposed between the axial section 70 of the lower spring supportflange 68 and the shoulder 74 is a spring support flange retainerassembly, generally designated by the numeral 76, and comprising a pairof semi-circular retainer members 78 and 80 as best seen in FIG. 2. Themembers 78, 80 extend approximately 180° around the housing 28 and areformed with an outwardly swaged portion 82 defining a radially inwardlyconfronting recess 84 adapted to nestingly receive the radiallyoutwardly projecting shoulder 74 on the housing 28. Additionally, theretainer members 78, 80 are formed with a radially inwardly extendingrecess 86 around the outer periphery thereof which is adapted tooperatively receive a suitable retaining or snap ring 88. It will benoted that the inner diameter of the axial section 70 of the springsupport flange 68 is greater than the outer diameter of the shoulder 74but is smaller in diameter than the outwardly formed swaged portion 82on the retainer members 78, 80. Accordingly, upon assembly of thesuspension device 10, the lower spring support flange 68 is movedaxially of the housing 28 to a position above the shoulder 74.Thereafter, the two retainer members 78, 80 are positioned around theshoulder 74 and the snap ring 88 is placed therearound in order tooperatively secure the members 78, 80 in place. The flange 68 maythereafter be moved downwardly until the axial section 70 thereofengages the swaged portion 82 of the members 78, 80, whereupon theflange 68 will be properly positioned along the housing 28. Asillustrated, a suitable resilient bearing pad 90 is provided on theradial section 72 of the flange 68 and is adapted for engagement withthe lower terminal end 58 of the spring 52. It will be noted that bothof the flanges 60 and 68 are retained in their respective axialpositions along the suspension device 10 under the influence of the coilspring 52 and as such the spring 52 is normally under a preselectedcompression load when it is installed on the device 10. In order toprovide for sound insulation and guide means for the spring 52, anelongated annular sleeve 92, fabricated of extruded rubber or othersuitable resilient material, is provided around the outer periphery ofthe dirt shield member 44, with the member 92 functioning to preventinterengagement of the spring 52 with the dirt shield member 44 andhousing 28 during cyclic operation of the suspension device 10. It willbe noted that by placing the spring 52 on the device 10 such that thegreater concentration of spring convolutions 54 are located out of axialregistry with the sleeve 92, a minimum amount of sleeve abrasion willoccur during operation of the shock absorber 12.

While it will be apparent that the preferred embodiment of the inventiondisclosed is well calculated to fulfill the objects above stated, itwill be appreciated that the invention is susceptible to modification,variation and change without departing from the proper scope or fairmeaning of the subjoined claims.

I claim:
 1. A vehicle suspension device comprising,a telescopic shockabsorber including an elongated tubular housing, a piston reciprocallydisposed within said housing and connected to one end of a piston rodextending axially outwardly from one end of said housing, attachmentmeans on the outer end of said piston rod and one end of said housingfor securing said device to the sprung and upsprung portions of anassociated vehicle, a tubular dirt shield supported on said one end ofsaid piston rod and extending coaxially of said rod and said housing,said dirt shield being larger in diameter than said housing and adpatedto telescopically receive the adjacent end of said housing therewithin,said dirt shield including a generally tubular-shaped dirt shield memberand a cap secured to said piston rod and said dirt shield member, saiddirt shield member being formed with a radially outwardly extendingshoulder adapted to operatively support one of said spring supportmeans, a helical coil spring extending coaxially of said housing andsaid dirt shield, with said dirt shield being disposed substantiallyentirely within said coil spring, and first and second spring supportmeans for operatively supporting said spring on said shock absorber, oneof said spring support means comprising an annular spring engagingmember having an axially extending portion arranged coaxially of saidshock absorber and a radially outwardly extending flange portion andadapted to have one axial end of said spring bear thereagainst, said onesupport means also comprising first and second circumferentiallyextending members disposed at least in part between the outer peripheryof said shock absorber and the inner periphery of said axial portion ofsaid spring engaging member, said circumferentially extending memberseach having radially outwardly projecting areas adapted to nestinglyreceive a radially outwardly projecting portion on said shock absorberand thereby at least in part support said annular member upon said shockabsorber.
 2. The invention as set forth in claim 1 which includes asecond radially outwardly extending shoulder on said housing adapted tooperatively support the other of said spring support means.
 3. Theinvention as set forth in claim 1 wherein said first and secondcircumferentially extending members are resiliently urged intoengagement with said projecting portion of said shock absorber by a coilspring.
 4. The invention as set forth in claim 1 which includes aninsulating sleeve extending around the outer periphery of said dirtshield, and wherein said coil spring is of the variable rate type andincludes a greater number of convolutions at one axial portion thereofthan at another axial portion thereof, and wherein said greater numberof convolutions are spaced axially away from said dirt shield and saidsleeve.
 5. The invention as set forth in claim 1 wherein each of saidcircumferentially extending members extends approximately 180° aroundsaid shock absorber.
 6. The invention as set forth in claim 1 whereinsaid one support means comprises the support means associated with saidtubular housing.
 7. The invention as set forth in claim 1 wherein theinner periphery of said annular portion of said spring engaging memberis larger in diameter than the outer periphery of said outwardlyprojecting portion of said shock absorber and smaller in diameter thanthe outer periphery of said circumferentially extending members whensaid members are mounted upon said shock absorber.